HackerTube: what it is and how Karpathy built it with Claude

HackerTube is a free video site that only shows YouTube videos Hacker News commenters have recommended over and over, 6,454 of them from 2007 to 2026. Andrej Karpathy built it in about two hours by talking to Claude Opus 5.5 in Claude Code, and you can use it now at hackertube.org with no account.

The post that started it

On Sunday, November 1, @karpathy called it a weekend hack. He was fed up with YouTube's recommendations, so "I had Claude filter down 43M comments over 20 years of HN" to the videos that keep coming up. The post has passed five million views and 43,000 bookmarks. My guess is a lot of those bookmarks are for the method, not the site.

His write-up on his blog fills in the pipeline. Claude downloaded every Hacker News comment from a public Hugging Face dataset, filtered them, ran Sonnet over them in a Claude Code Workflow, removed spam, and ended up with about 40,000 comments that recommend a YouTube video. Those comments point to the 6,454 videos, sorted into 150 topics.

What HackerTube does

Karpathy's post and blog list a few deliberate choices:

• Recommendations work without logins. Your viewing state stays in your own browser session.
• Each thumbnail is a frame from the middle of the video, not the uploaded thumbnail, which Karpathy describes as hyper-optimized through A/B tests.
• There's a "Longs" section for long videos, plus keyboard shortcuts.
• The data from the comment analysis is offered as one download, so you can hand it to your own agent and build a variant.

How to use it

1. Go to hackertube.org and start on the home page, where the For You recommendations live.
2. Use Categories to browse by topic, or Longs if you want something meaty for the evening.
3. Like videos, save them to Watch later, and check History to find something again.
4. Your state lives in the browser, so clearing site data or switching browsers should give you a fresh start.

How Karpathy built it

For anyone running a business, the process matters more than the site. In the post and an edit to his blog, he says his default is Claude Code's Mac desktop app with Opus 5.5 at Medium effort, and that he only talked to Claude and had it do everything. His own hands-on work was three browser chores:

His closing line: big projects that used to take weeks or months "can now be few-shotted for breakfast."

The Medium-effort detail got its own thread. @swyx pointed out which setting Karpathy uses and joked that "having strong opinions on effort levels is like the tabs vs spaces of our time." His advice is to tune it to taste. If you run Claude Code with helpers, our post on Claude Code subagent effort shows how to set effort per agent.

Build your own version

Karpathy's own suggestion is to give the exported data to your agent and ask for your version. A starting prompt for Claude Code, written by us and untested against his files:

Here is the HackerTube data export. Build me a static site that shows only
videos tagged with programming, math or history topics, ranked by how many
distinct HN comments recommend each one. Keep state in localStorage, no
accounts. Run it locally first and show me the page.

The same idea works on other piles of text, like a forum your industry trusts or years of customer emails. For more builds like this, see Simon Willison's Battle Drones game made with Opus 5.5 and the Opus 5.5 pixel art made from code.

My read

I like HackerTube, but the table is the part I keep coming back to. The parts Karpathy did himself were accounts, keys, a server and a domain: the decisions about where things live and who pays. The data work, which would once have been the whole project, took Claude a morning.

Plenty of small businesses have the same kind of buried value: years of reviews, quotes, emails or job notes that nobody has time to sort. Turning that into something useful is now an afternoon job, as long as someone owns the credentials and decides what "useful" means. If you want help finding which of your processes could use that treatment, New Face Design's free process audit is a good first step.